Teat length and penetration into teatcup during milking in Norwegian Red Cattle

Abstract

SummaryTeat penetration into transparent silicone rubber teatcup liners was recorded during milking of 90 cows on 15 farms. The cows were of Norwegian Red Cattle breed with mean teat length close to the average for the breed. The mean teat length was 54 and 48 mm for fore and rear teats respectively, and mean penetration at the end of milking was 104 and 94 mm. No significant correlation between initial teat length and teat elongation (difference between penetration and initial length) was found. This indicated that the teatcup liner was more stable on long teats than on short. The distribution of teat penetration at the end of milking showed that a large proportion of fore teats penetrated too far into the liner at the end of milking. The optimal liner length for Norwegian Red Cattle was ~ 150 mm.

Teat thickness changes may provide biological test for effective pulsation

“…These specifications are based, in part, on research results that link pulsator faults with increased infection risk. New infection rates were increased, for example, in the absence of pulsation (Bramley et al 1978;Reitsma et al 1981), or if the duration of liner closure was less thañ 300 ms (Reitsma et al 1981), or when liners were too short to collapse fully beneath the teat (Mein et al 1983(Mein et al , 1987Ronningen & Reitan, 1990), or when the d phase of pulsation was reduced to 72 ms (O'Shea et al 1984). Incidence of teat lesions was increased by faulty pulsation (Jackson, 1970) or if the d phase was < 290 ms (0steras et al 1995).…”